SCIENTIFIC SUMMAEY. 
661 
fragment worn and rounded in some of the prominent parts, and looked like 
a small 23ortion of a pine branch which had been exposed to rough treatment, 
so as to present a wasted surface deprived of the bark. It was entirely 
siliceous, and exhibited its vegetable structure most perfectly. Traversing 
the woody fibres were several short tubular masses swollen at the end, and 
marked more or less plainly with transverse rings. These Professor Phillips 
supposed to be flmt moulds of cavities left by boring shells, probably 
Teredinidce. It would appear that these animals must have begun their 
operations in a young state on the wood, when it was reduced to its present 
form and size ; for the moulds which remain in their holes appear to be 
quite small at the surface, and to expand internally. The writer of the paper 
becomes absolutely poetical in his speculations upon the remnant of extinct 
vegetation which he described. He writes : — “ Far away from the Cretaceous 
Sea of Albion, among the mountains previously uplifted in the W est, from 
which had flowed the great river of the W ealden, we see a forest of coniferous 
trees. Whirled and broken to fragments by the rushing stream which 
received their decaying stems, the ruins of the forest reach the sea, and some 
few pieces float far from the shore beyond the area of deposited mud and 
drifted sand. Attacked by xylophagous mollusks, and sinking to the ocean 
bed, one at least serves as the nucleus for organic growth and accretion.” 
Professor Phillips does not here refer to ordinary accretion ; he conceives of 
the block as first surrounded by organic matter, and then, when buried in the 
cretaceous deposit, serving as a centre of attraction for siliceous solutions, 
such as have more than filled to solidity the tissues of sponges. 
The Volcanic District of Chili . — Some short time since, M. Pissis, the great 
explorer of South American geology, transmitted to M. Elie de Beaumont an 
elaborate description of the volcanic regions of Chili. He found the volcano 
of Chilians again in a state of eruption. This is a very rare circumstance in 
the volcanoes of the Andes, where the eruptions generally succeed each other 
only at very long intervals. The present eruption, which is much more ex- 
tensive than the last one, commenced towards the end of last November, at a 
new point, situated about 200 metres below the summit of the grand cone, 
the new cone having towards the end of J anuary attained a height of 50 
metres. The lava escaping by two apertu’res near the summit, had already 
reached the vast glacier surrounding this massive volcano. The grand cone, 
which was covered with snow during the eruption, had the appearance of 
being completely bare, yet the snow had not been melted, but was covered 
with a great quantity of projected substances, which formed a layer over the 
snow of many decimetres in thickness. The alternation of glaciers with layers 
of scoriae are frequently met with in the volcanic cones of the Andes ; where- 
ever natural clefts occur, a great number of these layers may be seen succes- 
sively superposed. The volcano of Antuco, visited last year, had been in 
eruption on a small scale in 1863. As no solid bodies were being projected 
at the time of his visit, M. Pissis was enabled to examine the interior of the 
crater, and, favoured by a strong westerly wind, to observe it without being 
annoyed by the acid vapours which escape in abundance. The principal 
column of vapour proceeded from an aperture nearly circular, being recognised 
as that through which the lava had escaped. Its diameter was only from 
our to five feet ; all this portion was covered with yellow or bright red scoria'. 
